[Rockin Robbins]

Ok, here's the thing. You are approaching from 45° from the target's course. In order for him to have an AOB of 45° he would have to be right in front of you, bearing zero. Although that would only give you a gyro angle of 10° or so, the whole premise of constant bearing attacks is to minimize gyro angles.

Let's just use an example where he is traveling from left to right with respect to us. In order to do that we'll shoot when he is about 10° before being straight ahead, bearing 350. To calculate the AoB you subtract that 10° from 45° to get your TDC setting of 35°. There is no more accurate way to set it, that's the correct number no matter what tool you use.

Now just because you shot 10° before he bore zero doesn't mean necessarily that your torpedo is going straight up the zero line. That's where people get their brains sprained when thinking about the John P Cromwell or Dick O'Kane methods. The fact is, with both methods we don't know exactly what that torpedo gyro angle is going to be.

We don't have to because we're going to use the TDC to aim the torpedo for us and it will set the exact angle. It might be a couple of degrees one way or the other from zero, depending on target speed.

So now we have the AoB at 35° and it's starboard, because we are looking at the starboard side of the target. We presumably already have the target speed, so we enter that. And for a range, we need something, although it isn't very important what it is. I just pull the sight triangle down to render something like 1400 yards. The TDC has a brain fart when the range is zero.

Make sure you press the send info to TDC button after every entry. Now all you have to do is set your scope at the 350 bearing and wait for the target to cross the wire. Shoot as the juicy parts are in the crosshair.

You can check the attack map to see if you've made any stupid mistakes, typically entering a port AoB when you mean starboard. In this case (what a coincidence!) the TDC will think the target is traveling from right to left. It will aim way left of the target. You KNOW that the angle has to be to the right of where the target is now in order to lead it properly. A quick look at the attack map will prevent a lot of embarrassment.

The John P Cromwell method is just as accurate as any fancier method. Difficulty does not translate into better accuracy. The solutions rendered by John P Cromwell are correct and will result in a torpedo striking the part of the target you aim for if your inputs are correct. That makes it exactly as accurate as Solution Solver, Hunt and Peck (made that one up), conventional position keeper targeting or using angle solver charts.

In practice the Cromwell and O'Kane methods will be more accurate than other methods because they are extremely simplified techniques that reduce the number of steps, and hence the number of chances to screw the pooch, as far as possible. Each step necessary to perform a procedure is an opportunity for error. Fewer steps means fewer errors.